IfVar

The <IfVar> element makes operations conditional on whether a variable exists and optionally matches a given value.

Using <IfVar> does not change the context (the current position in the document).

Attribute Description
containsRegex The variable must contain a match to this regular expression.
matches The variable must match this value exactly.
matchesRegex The variable must match this regular expression.
negate Set this attribute to true to perform the child operations when the variable does not exist or does not match a given value.
var The name of the variable to check.

The following example adds a field to the document metadata when the value of a variable named "reference" matches a regular expression.

<FieldStandardization>
    <IfVar var="reference" matchesRegex="http.*">
        <AddField name="referenceUrl" value="$(reference)" />
    </IfVar>
</FieldStandardization>